I have one because I rate and value the BBC (dreadful TV news excepted).
I love radio 4 and listen live and also through Sounds. Whilst you do not need a licence for radio, it is funded through the licence fee, so if you care about it, you need to help fund it via the licence fee. I also have Spotify.
As a teacher and tutor, I also use BBCLearn, which is a fabulous resource, again funded out of the licence fee.
The BBC is also a bastion of training and promoting talent, especially behind the scenes. If you are a young person wishing to work in TV from sets to lighting, to camera to script writing, the BBC is your best bet for an apprenticeship. Without it we would lose so much talent to America - because the streaming sites are based there.
£170 is less than £15 per month and I think this is great value, especially as so much of the content is new and fresh. So much stuff on streaming sites is either regurgitated (old BBC/ITV/Channel4/American networks) or very poor quality (terrible plot-lines and scripts).
I occasionally watch some live TV and stuff on iplayer, but also have Netflix, Disney+ and AppleTV.